System information

GRAVITAS SABRE SERIES
INSTALLATION &OPERATING MANUAL
Manual No. SABRE-4 Page 15 11/27/07 sabre-man
1.2.1.7 Voltage and frequency mode
The STS has two inputs and one output. The two inputs are from Mains Utility and Inverters; the output is the system
output. The STS will continuously detect Mains voltage and Inverter voltage in order to decide the system’s supply
mode. If both Mains and Inverters are normal, the Mains has priority to decide the operation status of the system. In
other words, the STS will firstly consider the Mains status to decide the system’s running voltage and frequency.
Following confirmation of the voltage and frequency, the over/under voltage and over/under frequency are set as
follows:
Over/under voltage window
120VAC 240VAC
Default Voltage
110V/115V/120V 208V/220V/230V/240V
Activate 138VAC 276VAC
Over Volt
Recovery 134VAC 268VAC
Activate 89VAC 176VAC
Under Volt
Recovery 93VAC 184VAC
Over/under frequency window
System frequency
60Hz 50Hz
Frequency high threshold 61.5Hz 51.25Hz
Frequency high back 61.2Hz 51Hz
Frequency low threshold 58.5Hz 48.75Hz
Frequency low back 58.8Hz 49Hz
Voltage Transfer Window
The STS will transfer to the auxiliary source if the priority input voltage exceeds a preset value, the over voltage and
under voltage limits are as follows:
120VAC 240VAC
Adjustable range
110V 115V 120V 208V 220V 230V 240V
Adjustable range 117~127 122~132 127~138 220~240 233~252 244~264 254~276Over
volt
Default value 127 132 138 240 252 264 276
Adjustable range 89~105 93~110 100~114 176~198 176~209 185~218 193~228
Under
volt
Default value 89 93 100 176 176 185 193